The present invention relates to devices for connnecting a back structure to one or more air cylinders, it particularly relates to devices for the attachment and release of one or more air cylinders to and from a back structure, more especially to and from the back of a stabilizer jacket.
For some time systems have been known which allow one or more suitably arranged air cylinders to be attached to and released from a back structure which is then either put on directly via suitable belts or is connected to a stabilizer jacket of known type. The latter solution, in particular, has the greatest advantages, both from the point of view of practicality and of comfort, and is certainly the most commonly used nowadays. Attachment and release of the air cylinders to and from the back structure must, of course, be as simple and quick as possible.
In order to achieve this rapid release numerous systems have been designed in the state of the art. Particularly significant in this respect are those described in the Dutch patent application 8503022, in the French patent application 9209740 and in the Italian patent application RE91A00071.
The Dutch patent application 8503022 describes a device formed by a carrying element and by a rod which can be inserted therein, the secure connection of which is provided by a ratchet which can be released by pulling an appropriate chain.
The French application 9209740 describes an attachment system consisting of two threaded pins located on the air cylinder or cylinders, and coupled to a pair of nut- and bolt fasteners inserted in the back structure; in this case the attachment is released by pulling a small cord connected to two hooks inserted in the nut- and bolt fasteners.
In the Italian patent application RE91A00071 the attachment involves elements located on both the air cylinder or cylinders and the back structure, locking one inside the other; one of these interlocking pairs has a pin and recess for accommodating the pin, respectively. The pin can be disengaged from the recess, resulting in the release of the attachment, by pulling on a handle.
As may be noted from the above description, the common factor in the three abovementioned devices is that the release mechanism is actuated by exerting a pulling force. Thus, systems of this type have the common disadvantage that they are relatively vulnerable to knocks or other accidental action which might inadvertently unlock the attachment mechanism and are, therefore, not very reliable.
Undoubtedly reliable, from the point of view of the stability of the attachment, are the systems described in U.S. Pat. No. 4,640,215 and in the Italian Patent for a utility model No. 199912. However, both these systems do not allow, or at least not without difficulty, the air cylinder to be rapidly disengaged from the stabilizer jacket, on the contrary (especially in the case of the U.S. patent) requiring the help of a second person to disengage the air cylinder or, at the very least, requiring the jacket to be taken off in order to do so.